Rotary breech mechanism for power generating propulsive charges



y 176, 1940- R. A. COFFMAN 2,208,496

ROTARY BREECH MECHANISM FOR POWER GENERATING PROPULSIVE CHARGES FiledApril 16, 1955 4 Sheets-Sheet l i' I03 Invenfor RoscoE A. CoFFMAN,

AH-orneya 1 y 1940. R. A. coFFMAN ROTARY BREECH MECHANISM FOR POWERGENERATING PROPULSIVE CHARGES Filed April 16, l9 35 4 Sheets-Sheet 2RoscoE A. COFFMAN AHov-neys July 16,1940. R. A. COFFMAN 3 ROTARY BREECHMECHANISM FOR POWER GENERATING PROPULSIVE CHARGES Filed April 16. 1935 4Sheets-Sheet 3 f July 16, 1940. CQFFMAN 2,208,496

ROTARY BREECH MECHANISM FOR POWER GENERATING PROPULSIVE CHARGES FiledApril 16, 1935 4 Sheets-Sheet 4 Patented July 16, 1940 Zittfitt RoscoeAlexander (Cofiman, Pittsburgh, Pa.

Application April 16, 1935, Serial No. 16,726 In Great Britain January18, 1935 20 Claims.

This invention relates to a method of and means for generating anddelivering propulsive charges, and it has for its object to providehighly efficient means for generating a plurality of propulsive chargesin controllable and ordered succession; for eifecting the thoroughscavenging of the apparatus after the delivery of one charge and priorto the generation of another charge, and for rendering it possible toutilize in a highly facile manner the unit charge shells constitutingthe subject matter of my copending application, Serial No. 581,032,filed December 14, 1931, and particularly when used in connection with astarter device of the type shown in my United States Patent No.1,776,228.

Further detailed objects and advantages of the invention will be setforth in the following specification.

In the accompanying drawings. Figure 1 is a plan view of an apparatusconstructed in accordance with the invention. Figure 2 is a sideelevation thereof. Figure 3 is a view partly in front end elevation andpartly in vertical section.

Figure 4 is a detailed sectional 64 of Fig. 5.

Figure 5 is a fragmentary rear elevation. Figure 6 is a fragmentarylongitudinal sectional view through the main barrel, upon line 30 6-6 ofFig. 8.

Figure 7 is a sectional view through a dashpot hereinafter described.

Figure 8 is a view partly in side elevation and partly in sectionlooking from the opposite side 35 than that illustrated in Fig. 2 andwith certain of the parts omitted.

Figure 9 is a diagrammatic view of the electrical connectionshereinafter described.

' Figure 10 is a section on line Ill-I0 of Fig. 3.

40 Figure 11 is a detailed sectional view through the scavengingcylinder through the line l|--ll of Fi 1.

Figure 12 is a plan view of the apparatus with the magazine removed andthe breech block 5 thrown to an inoperative position.

Figure 13 is a detailed sectional view of the cam slide taken on theline |3-l3 of Figure 15.

Figure 14 is a detailed sectional view of the cam slide taken on theline M-ld of Figure 15;

50 and g Figure 15 is a top plan view, partly in section,

of the cam slide and its cooperating parts.

Like numerals designate corresponding parts in all the figures of thedrawings,

view upon line The purpose of the present invention is to pro- (Cl. Gil-M) vide a mechanism comprising a barrel, a magazine adapted to containshells of the character of that shown in my copending application.aforesaid, means for automatically operating the magazine to bring theshells successively into 5 firing relation to the barrel, means forinsuring against the closing of the firing circuit until the shell hasbeen properly positioned with respect to the barrel, means for insuringthe thorough scavenging of the barrel prior to the bringing of anothercartridge into operative relation of the same, and. means forcontrolling the speed of operation of the various parts to bring about avariable rate of speed where desired, all of the foregoing operationsbeing carried out under the 15 influence of power derived from thecharge itself.

The shells used are described as containing a combustible fuel incontradistinction to a quick flash high power detonating explosive. Thefuel used is described as consisting of a combination nitrocellulose andnitroglycerine grains which may be of varying sizes or degrees ofaeration to bring about desired variations in the rate of burning sothat where desired some of the charge may be bodily blown over toanother point to be there consumed. Unit charge shells of this characterhave a wide range of applicability and usefulness in that theyconstitute what is in effect packages of stored up power which may beused to operate other mechanisms without the shock and jar which wouldbe inherent in the use of truly explosive charges.

In providing a mechanism adapted to developand deliver the power fromunit charge cartridges of this character, I may utilize a structure suchas that shown in the accompanying drawings and comprising-a barrelS'that is threaded at its forward end 6 for connection to a deliverytube (not shown) by which the generated gases or a part 40 of the fuelitself, may be conducted to a mech-- anism to be operated, such as, forexample, the engine starter referred to above.

At the rear end of the barrel there is preferably provided as indicatedat 8, a combustion cham-' her. The barrel is provided at one side with aneck extension 9 having a seat It adapted to receive the tapered end ofthe shell receiving liners H of a shell carrying magazine l2, one of theshells being indicated .at l3. When a shell is discharged its burnablecontents pass into combustion chamber 8 and are there burned andcontinuing to burn within the closed system untilcompletely consumed,the generated gases passing outof the barrel 5 to perform whatever workis required of them. Some of these gases act upon a piston l4 that ismounted in a cylinder [5 which extends downwardly from combustionchamber 8. This piston is in turn connected, at l6, to a head H.

In the accompanying drawings, the barrel 5 is illustrated as extendinghorizontally, and the magazine is illustrated as being mounted to rotatein a horizontal plane parallel to and above the barrel. However, sinceone of the most important uses of the apparatus is in conjunction withairplane engine starters, it follows that the entire mechanism must beoperable in any and all attitudes of the airplane.

The head I! is connected at its outer end to two rods l8 and I9, seeFigure 3 and Fig. 5, and these rods are in turn connected at their otherends to a breech block 20, Fig. 3, which carries an electrical firingpin 2i. In my application Serial No. 581,032 I have described the shellas being capable of being electrically-'- fired, and in Fig. 9 of thepresent application I have diagrammatically illustrated an electriccircuit comprising a manually operable control switch 22, battery 23,conductors 24, and contact blades 25 and 26 which operate automaticallyin a manner hereinafter described.

heating of a bridge wire in the manner shown in my aforesaid applicationand well known in the electricdetonator art.

The breech block 20 of Fig. 3 is pivotally connected, at 21, to the rodl8 and is held in place upon rod l9 by a winged thumb nut 28. Normally,this thumb nut is prevented from turning by a detent 29 which straddlesits wings, but when it is desired to remove the magazine from itsoperative position and reload, the detent 29 can be depressed enough tofree the wings of the nut 26 and permit the same to be turned so thatthe breech block can be thrown back and the magazine removed as a wholefrom the rod Ill. The detent 29 is preferably continued beyond itssecuring screw 30 to form a tongue 3| adapted to engage in the notchesof and look a nut 32 by which the firing pin is locked in operativeposition.

The barrel 5 and the combustion chamber 8 are preferably cast integrallyin a block generally outlined at 5' of Fig. 5 which block carries atransversely screw threaded lug 33, Fig.

3, and by referring to that figure, it will be seen that a sleeve 34 isthreaded into the lug 33 and binds a plate 35 between said lug and ashoulder 36 of said sleeve. The rod I9 passes through the sleeve andcarries a collar 46 which lies within the hub 4| of the magazine. Themagazine consists of the hub 4|, its radial rib 42, the group ofcylinders (in this case twelve, 43) and the liners H for said cylinders.These liners are provided with the forward beveled ends Ha adapted toengage the seat III of the neck extension 9 of the cylinder.

Referring to Fig. 8, itwill be seen that the plate '35 is channelled, at35a, for the receptionaecaeee piston carrying with it a plate 49 which,in such forward movement of the piston compresses a spring 50 into acup-like element 5| that is carried by a lateral extension 52 of thebarrel 5. The plate 49 carries a slide 53 shown in phantom in Fig. 6 andwhich, as may be seen from an inspection of Figures 3, 5, 8, 13, 14 andis provided with two cam surfaces 54 and 55. The cam surface 54 acts,upon the return movement of rod 46 under the influence of spring 50, tothrust a locking pin 56 upwardly when the lower end of said locking pinrides up the incline 51.

In the normal position of the parts, i. e., the position in which theyare shown in Fig. 8 and which is the position in which they lie when theparts are at rest, the pin 56 is elevated and at this time the short end58 of a bell crank lever 59 has been thrust upwardly to throw the pawl60 toward the right, said pawl being pivoted to the bell crank lever 59,at 6|, and being actuated by a spring 62 to cause its nose to engage theteeth 63 of a sleeve 64 carried by the hub 4| of the magazine, thefunction of the. pawl and bell crank lever being to impart the necessarystep by step turning movement of the magazine.

However, when the slide 53 moves forwardly and the pin rides onto thelower level of the cam 54, the bell crank lever is moved toward the leftto cause the nose of its pawl to engage the next operating tooth. Thisaction takes place under the co-acting influence of a spring 65 that ishoused in a casing 66 and which bears between the top of said casing anda collar 61 on a lock rod 66. The upper end of this lock rod is adaptedat the proper time to disengage and re-engage in the corresponding oneof the opening 69 of the web 42 of the magazine. This rod is alsoprovided with a finger piece 10 upon its lower end by which it may bemanually operated when it is desired to free the magazine and permit itsrotation by hand, if desired for any reason. The thrust of the spring 65is in opposition to the thrust of a spring H which bears between thecollar 61 and the forked end 12 of an arm 13 pivoted at I3. The arm 13lies in 'the path of movement of the bell crank lever 59.

Thus, when slide 53 moves toward the left and pin 56 descends, the armI3 is lowered, tension is released upon spring H, and spring 65 'acts tothrust the lock rod 68 out of its opening 69 and this same action causesthe bell crank lever 59 to move toward the left to take hold of thesucceeding one of the teeth 63. Then, when the slide 53 moves toward theright under the influence of spring 50, initial upward movement of thepin 56, through the bell crank lever, turns the magazine enough to movethe opening 69 out of engagement with the lock rod; this action takingplace before the tension imposed upon spring II by the movement of arm13 is suflicient to overcome the action of spring 65.

However, continued upward movement of the pin 56 and arm 13 result inplacing such tension upon spring II as to overcome spring 65 and thelock --rod is moved into contact with the face of the web 42 so thatwhen the next opening 69 comes aeoaeee into alignment with said rod (andat which time one of the shells will be properly aligned with cylinderextension 9) said lock rod will snap into said opening and lock themagazine against turning movement.

A dashpot "I is disposed in parallel relation- ,ship with the barrel 5and may be formed as a part of the t arrel casting. The construction ofthis dashpot is illustrated in Fig. 7 from which it will be seen that apiston rod I6 passes through a stufiing box 11 and carries a piston I8upon its inner end. This piston, provided with a suitable packing ringI9 which may be of leather, is moved from its normal position by theaction of spring 00 of Fig. 7.

A valve plate 8| that is normally closed by the action of a spring 82controls ports 83 formed through the said piston. A transversely groovedcontrol pin 86 is carried by the cylinder head I5 and the piston rod I6is made of tubular formation for the reception of this pin. It will beobserved that this pin has a threaded head. 85'

- that is screwed into the cylinder I5 so that this and establishescommunication between the interior of the cylinder, at 87, and theinterior of the cylinder, at 88, the flow being through the port 86 andalong the pin 80 which is made to fit so loosely in the bore of thepiston rod that flow of the cylinder content, which may be oil,glycerine, or other suitable lubricant, may take place past said pin.The purposes and advantage of this arrangement will be presentlydescribed.

A lateral extension 09 of the cylinder carries a compensating cylinder90 in which a piston 9| is disposed. A spring 92 urges this pistoninwardly and the interior of the cylinder 90 is in communication withthe cylinder I5 through ports 93 and 98. The function of the piston 9|and the spring 92 is to compensate for the variation of cubic capacityin the left hand end of cylinder I5 due to the movement of the pistonrod I6 out of said cylinder. As this takes place, the piston 9| movesinwardly enough to force an equivalent quantity of liquid from cylinder90 into the portion 81 of cylinder I5. At the completion of the firingof one charge, the spring 00 will have moved the piston rod I6 outwardlyto its limit of movement and the outer end of said piston rod will haveimpinged upon and thrust forwardly upon rod 95, Fig. 8, that is movablethrough 8. lug 96 of the barrel 5 and the function of which is to presscontact strip 25 into engagement with the contact strip 26, these stripscor-' responding to the like parts illustrated in the diagrammaticFig.9, and constituting a part of.-

to hold these parts in proper parallelism with each other, I provide arod or heavy wire 91, a lateral extension of which fixedly engagespistonrod 16, at 90, and the longitudinal run of which has slidingengagement, as indicated at 99, in the rod 48. In addition, the block60a is provided with a lateral web I00 which embraces the firing pin 2|and to relieve the pressure of the breech block 20 upon said shells andthereand slides along rod I6.

when the block 48a moves outward, a flanged surface 49a of said block,which is suitably bev- I5, and after the flanged surface passes thelatch plate, said latch plate is moved by a spring I02 to cause it toengage behind the flanged surface 59a of block 60a, thus coupling thepower storing means to said piston rod It and for the purpose hereindescribed.

The result is that when the block starts to move rearwardly again underthe influence of spring 50, it carries the latch plate IM and the pistonrod It with it. Therefore, the return movement of the parts is resistedand cushioned by the action of the dashpot and this return movement cantake place only as fast as liquid can be displaced from 08 by flowingpast grooved control pin 8d and out of port 86 into the chamber 07, andthis movement can in turn be made a variable one by suitably shaping thepin 06, it being readily understood that this pin is removable and maybe replaced by a pin differently grooved to suit the conditions desiredfor controlling the flow of liquid. It may be found to be desirable tohave some portions of this movement more rapid than others, and bysuitably shaping pin 84 throughout its length and with liquid controlpassages or grooves of varying size and capacity, any desired variationmay be had. Rearward movement of rod 88 and piston rod I6 together,continues, until a tail I 03 of the latch plate IOI engages an inclinedplate I05 which projects from compensating cylinder 90, see Figures 3and 8.

This plate is so disposed as to constitute'a cam surface over which thetail I 03 rides to turn latch plate I0l against the tension of itsspring and move it out of engagement from. beneath the flanged surface69a of the block 40a. This takes place near the rearward limit ofmovement of the parts and when it takes place the piston rod of thedashpot is released from rod 40, and the spring 00 begins to thrust thepiston I9 of the dashpot forward as fast as liquid can be displaced from0'I to 80 through ports 83. However, it will be seen that the electriccircuit is above described, a latch I00 that is carried by block 60a,Fig. 1, engages a cam disk I05 that is pivoted, at I05 upon the barreland moves said cam disk against the action of a spring I08 to cause acam extension I0I of said disk to thrust a piston rod I08 inwardly in asmall cylinder I09 that is mounted upon the top of the barrel 5. Thelatch I04 is spring actuated outwardly, as indicated at mm. Thiscylinder is a scavenging one and the piston rod carries a piston I I0which is normally thrust outwardly by spring Ill and which when thrustinwardly against the tension of said spring uncovers a port H2 so thatthe barrel may be fully scavenged by the escape of any unburned gasesthrough port H2 and a port H3 in the top of said cylinder.

In order to free the shells of engagement by after also to impart-bodilylifting movement to the magazine away from the plate 35 and its asbestoscovering or layer 44, prior to rotation of the magazine, the cam 55 ofslide 53 (Fi 8) is provided. This cam acts upon the tail H5 of a rockingdog H6 that is mounted within a U-shaped block or collar I", said blockin turn embracing and being secured to rod I9 by screws H8, see Figs. 3,5 and 10.

When the cam 55 is in the position to the right as shown in Figure 8,the tail H5 of the rocking dog I I6 which has previously passed from thehigh point of the surface 55a of said cam 55, then assumes the positionshown adjacent the vertical surface 53a of said cam 55, in whichposition the magazine and the breech block have been lowered or returnedto normal position for the firing of another cartridge if and when allother parts'of the mechanism are in proper operative relation. As thecam'55 moves to the left of the position shown in Figure 8, as will behereinafter set forth, the vertical surface 53a of said cam will contactthe tail H5 of the rocking dog H6 and move the same out of the path ofsaid cam member 55 and against the tension of the spring H9, hereinafterreferred to more in detail, thereby rocking said spring actuated dog H6and permitting thecam member 55 to continue its movement to the left andfinally permitting the tail H5 to assume a position over the flathorizontal surface of the cam 55 ready to be acted upon by the inclinedsurface 55a of said cam for lifting the tail H5 and the spring dog, andalong with it rod I9, the magazine and the breech block as herein setforth, and this as the cam 55 returns to its normal position at theright, as shown in Figure 8.

The rod l9 when lifted by the cam 55 as described, also carries with itthe head I! and the rod I8, as will be readily understood, and

this movement of these parts first imparts lifting movement to thefiring pin and breech block mechanism away'from the magazine, andfurther due to the engagement of the collar 40 with the shoulder 43a ofthe magazine, lifting movement is also imparted to said magazine for thepurpose intended and as heretofore set forth. It is to be noted that therocking dog H6 is held in normal position withits nose or projection I20resting against the block or collar H"I which acts as a stop in onedirection for the dog H6, said dog being urged in said. direction bymeans of a spring H9 as clearly shown in Figures 10 and 15 of thedrawings.

It will be readily understood from the above description that when thevarious parts are in normal position as shown in Figure 8, the magazineis in locked relation with the plate 35 (lock rod 68 engaging within oneof the openings 69 in the web 42 of the magazine), and the unit chargeshell to be fired is in proper alignment with the side outlet of thebarrel into whichsaid unit charge is discharged;-also that locking pin56 is in its uppermost position urging the bell crank lever to theright, the position it assumed after its previous operation of movingthe magazine one step to bring the unit charge,

now to be fired, in the relative position just mentioned.

Furthermore, it is to be understood that at this time the block 48a isdisconnected from the piston rod I6 of the dashpot I5 and that said potcylinder, and this for the purpose of holding contacts 25 and 26 of theignition circuit in closed position, so that when the manual switch 22is closed, the ignition circuit will be completed for the purpose offiring the unit charge shell which is now properly positioned as justdescribed.

Upon ignition of this unit charge shell and the discharging of the unitcharge into the barrel, pressure is built up for the purposes intendedhere, and some of this pressure is used for moving a piston 41 to storeup power in a spring 50 which afterwards serves to return the piston 41to its normal position as shown in Figures 6 and 8.

This piston 41 while storing up power in the spring 50, also moves thetubular rod 40 and its block 48a to the left where the block 40a makestemporary connection with the dashpot piston rod I6 through theoperation of the parts 09a, 4912, IN, and I02, so that when the fluidpressure in the barrel has accomplished its work and is exhausting, thestorage spring 50 then comes into action to return the piston 41, rod 48and block 48a to their normal position, and moving with them at thistime and in the same direction to the right, is the dashpot piston rodI6 due to the connection 49a, IM and I02 just referred-to, all these.parts just described being moved to the right under the influence of thedashpot structure described herein, and for the purpose of allowing forthe proper amount of time for exhausting the barrel and for theoperation of the various mechanisms to be operated prior to the firingof another charge. It is well to note here that immediately upon theinitial movement of the dashpot piston rod I6 to the right, the ignitioncircuit at contacts 25-26 is open, and these contacts are not closedagain until the piston rod, I6 is released from its connection withblock 48a and returned again to the position shown in Figure 8, saidrelease being accomplished by means of the engagement of the tail I03 onthe latch l0I with the stationary cam or inclined plate I04, and this atthe end of the return movement of parts 40a, 48 and 41.

During the return 'movement of these parts under the influence of thepower storage spring 50, the cams and 55 come into play due to themovement of these cams in the same direction to the right (said camsbeing carried by a plate 49 moving with the piston 01), whereupon cam 55operates as herein described to first move the breech block and firingpin away from the magazine and thereafter move the magazine away fromthe barrel, so as to permit easy rotation of the magazine one step tobring another unit charge shell in proper position to be fired as justdescribed. As to the cam 50, this cam contacts pin 56 and lifts the sameinto engagement with the bell crank lever 59 for moving the same to theright so that the pawl and ratchet 60-63 may operate to move themagazine one step as just set forth, said bell cran'klever and its p wl50 having previously been moved to the left to engage the pawl withanother tooth of the ratchet wheel 63 at the time pin 56 was lowered outof contact with the short arm of the bell crank lever and when the cam54 had been moved to the left topermit of such lowering.

What I claim and desire to secure by Letters Patent is:

l. A structure of the character described comprising a barrel providedwith a seating portion, a rotatably mounted magazine provided with aplurality of liner cylinders each ontaining a unit charge shell of thepressure generating type, said cylinders being adapted to eachsuccessively engage the said seating portion, means aaoaace to ignitethe said unit charge shell when each cylinder is in such seatingrelation, pressure operated means utilizing at least a portion of thepressure generated by the unit charge so ignited to effectively seal thesaid engaged cylinder and the said seating portion in leak proofoperative position, a plate over which the said liner cylinders rotate,and an annular web carried by said plate and cooperating with thesealing ends of the combustion chamber, a piston in said cylinderoperated by the pressure fluid passing through said port, a rod to whichthe piston is connected, a spring for resisting movement of said rodand. piston in which power is stored by the movement of said pistonduring its fluid pressure stroke, an automatic switch, a dashpotcylinder in parallelism with the first-named cylinder, a piston in thedashpot cylinder, a piston rod for the'dashpot piston adapted to closethe automatic switch when in its normal pro-.

jected or released position, latch mechanism between the flrst-named rodand the piston rod of the dashpot cylinder adapted to lock the two totravel together for opening said automatic switch during initial reversemovement of the first-named piston under the influence of said spring,means for releasing the latch mechanism after such reverse movement hascontinued for a predetermined period, and means for projecting thepiston rod of the dashpot cylinder after such release for moving saidautomatic switch to its normal closed position.

3. A device of the characterdescribed comprising a main barrelconstituting a combustion chamber, a magazine adapted to hold aplurality of unit charges adapted to generate fluid pressure whenignited and burned, means for automatically bringing each unit chargesuccessively into operative relation with said combustion chamber, meansfor discharging a unit, charge into said chamber when in operativeposition, an electrical circuit for igniting said unit charge, a manualcontrol switch in said-circuit and a normally closed automaticallycontrolled switch therein, a cylinder arranged in parallelism with saidbarrel, a direct communicating port between said cylinder and thecombustion chamber, a piston in said cylinder operated by the pressurefluid passing through said port, a rod to which the piston is connected,a spring for resisting movement of said rod and piston in which power isstored by the movement of said piston during its fluid pressure stroke,a dashpot cylinder in parallelism with the first-named cylinder, apiston in the dashpot cylinder, a piston rod. for the dashpot pistonadapted to close the automatic switch when in its normal projected orreleased position, latch mechanism between the first-named rod and thepiston rod of the dashpot cylinder adapted to lock the two to traveltogether for opening said automatic switch during initial reversemovement of the first-named piston under the influence of said spring,means for releasing the latch mechanism aftersuch reverse movement hascontinued for a predetermined period, and means for projecting thepiston rod of the dashpot cylinder after such release for moving saidautomatic switch to its normal closed position.

" 4. A structure as recited in claim 3 in combination with a feedingmechanism for the magazine, and a lock mechanism for the magazine, andmeans for actuating both of said mechanims under the return movement ofthe firstnamed piston and its rod.

5. A structure as recited in claim 3 in combination with a lockingmechanism for the magazine,and a feed mechanism for the magazine, aslide movable with said piston actuated rod, cams carried by said slide,and means actuated by said cams for operating the locking and feedingmechanisms of the magazine.

6. A structure as recited in claim 3 in combination with a compensatingmeans for the dashpot for automatically supplying to the dashpotcylinder an amount of liquid equal to that displaced by that portion ofthe piston rod which has been projected from the dashpot.

7. A structure as recited in claim 3 in combination with a variable flowmechanism for the dashpot piston by which the inward movement of thedashpot piston. is rendered variable in speed.

8. A device of the character described comprising a barrel, a cylinderin parallelism .therewith, a piston in said cylinder, a port between thebarrel and cylinder, a rod actuated by said piston, a spring resistingmovement of said rod, a slide carried by said rod, a pair of camscarried by said slide, a rotative magazine containing a plurality ofunit charge shells, a firing pin and breech block mechanism positionedabove said magazine and adapted to cooperate with each of said unitcharge shells in succession for igniting the same, an endwise movablerod axially disposed with respect to the pin and breech mechanism awayfrom the magazine prior to the turning movement of said magazine.

9. A structure as recited in claim 8 in combination with a breech blockconnected to said rod, said rod acting to move the breech block awayfrom the magazine and while maintaining said relationship to thereaftermove the magazine away from the barrel and prior to the tuming movementof said magazine for the purposes intended. I

10. A device of the character described comprising a barrel the rear endof which -constitutes a combustion chamber, a magazine mounted forrotation about an axis perpendicular to the axis of the barrel, saidmagazine comprising a plurality of chambers adapted to receivepropulsive charge shells, said barrel having a side outlet with whichsaid chambers are brought successively into alignment, a breech blockextend- 70 ing across the rear of said magazine, a pair of rods to theend of one of which said breech block is pivotally connected and to theend of the other of which said breech block is releasably connected, ahead to which the opposite ends of J said rods are connected, a pistonfor imparting movement to said head and to the breech block to move thebreech block toward the magazine,

' a cylinder in which said piston is mounted, said cylinder being incommunication with the barrel, a second cylinder in parallelism with thebarrel and disposed to one side thereof, a power storing. meanscomprising a piston movable in said cylinder and a spring compressed bythe movement of said piston, to permit said piston to return to itsnormal position, a member carried by one of said rods, and cam meansactuated by the power storing means for moving said member to move therod in such manner as to initially move the breech block away from themagazine and thereafter move the magazine away fromv the barrel topermit easy and effective rotation of said magazine for positioning ashell in proper firing relation with said barrel.

11. A structure as recited in claim 10 in combination with a feedmechanism for the magazine, and a cam mechanism actuated by the powerstoring means upon its return stroke for actuating said feed mechanism.

12. A structure as recited in claim 10 in combination with a feedmechanism for the magazine and a locking mechanism for the magazine, andcam means actuated by the power storing means upon the return stroke ofthe latter -'for actuating the feed mechanism and said locking means. I

13. A structure as recited in claim 10 in combination with a retardingmeans comprising a piston and rod adapted to be coupled to the powerstoring means to permit proper operation of the several mechanisms, andinterengaging guides between the power storing means and said rod of theretarding means to insure proper coupling of said parts for the purposesintended.

14. A structure as recited in claim 10 in combination with a scavengingvent upon the barrel to permit escape of any unburned gases, acontrolling means for the same, and means actuated under the returnmovement of the power storing means and actuating said controllingmeans.

15. A device of the character described comprising a barrel the rear endof which constitutes a combustion chamber, a magazine mounted forrotation about an axis perpendicular to the axis of the barrel, saidmagazine comprising a plurality of chambers adapted to receivepropulsive charge shells, said barrel having a side outlet with whichsaid chambers are brought successively into alignment, a breech blockextending across the rear of said magazine, a pair of rods to the end ofone of which said breech block is pivotally connected and to the end ofthe other of which said breech block is releasably'oonnected, ahead towhich the opposite ends of said rods are connected, a'piston forimparting movement to said head and to the breech block to move thebreech block toward the magazine, a

cylinder in which said piston is mounted, said cylinder being incommunication with the barrel,

9. second cylinder in parallelism with the barrel and disposed to oneside thereof, a power storing means comprising a piston movable in saidcylinder and a spring compressed by the movement of said piston, amember carried by one of said rods, cam means actuated by the powerstoring means for moving said member to move the rod in such manner asto initially move the breech block away from the magazine and thereaftermove the magazine away from the barrel, aliashpot cylinder having apiston therein and a piston rod, a firing pin carried by the breechblock, an electric circuit in which said firing pin is included, circuitmaking and breaking means in said electric circuit. means for actuatingthe piston and piston rod, and means actuated by the piston rod of thedashpot for closing the circuit of said last named circuit making andbreaking means.

16. A device of the character described comprising a barrel the rear endof which constitutes a combustion chamber, a magazine mounted forrotation about an axis perpendicular to the axis of the barrel, saidmagazine comprising a plurality of chambers adapted to receivepropulsive charge shells, said barrel having a side outlet with whichsaid chambers are brought successively into alignment, a breech blockextending across the rear of said magazine, a pair of rods to the end ofone of which said breech block is pivotally connected and to the end ofthe other of which said breech block is releasably connected, a head towhich the opposite ends of said rods are connected, a piston forimparting movement to said head and to the breech block to move thebreech block toward the magazine to hold said breech block in properfiring relation to said magazine, a cylinder in-which said piston ismounted, said cylinderbeing in communication with the barrel, a secondcylinder in parallelism with the barrel and disposed to one sidethereof, a power storing means ecomprising a piston movable in saidcylinder and a spring compressed by the movement of said piston topermit said piston to return to its normal position, a member carried byone of said rods, cam means actuated by the power storing means formoving said member to move the rod in such manner as to initially movethe breech block away from the magazine and thereafter move the magazineaway from the barrel to permit rotation of said magazine, a dashpotcomprising a cylinder, a piston therein, a piston rod carried by saidpiston, a spring tending to thrust said piston rod outwardly, a circuitclosing means in the path of movement of said piston rod adapted to beclosed at the completion of the outward movement of said piston rod andmeans for locking the piston rod and the power storing means together insuch manner as 'to open the switch during the initial reverse movementof the piston rod and to cause the dashpot to retard the return movementof the power storing means and thus allow time for proper operation ofthe various mechanisms.

17. A device of the character described com-' prising a barrel the rearend of which constitutes a combustion chamber, a magazine mounted forrotation about an axis perpendicular to the axis of'the barrel, saidmagazine comprising a plurality of chambers adapted to receivepropulsive charge shells, said barrel having a side outlet with which,said chambers are brought successively into alignment, 8. breech blockextending across the rear of said magazine, a pair of rods to the end ofone-on which said breech block is pivotally connected and to the end ofthe other of which said breech block is releasably connected, a head towhich the opposite ends of said rods are connected, a piston forimparting movement to said head and to the breech block to move thebreech block toward the magazine, a cylinder in which said piston ismounted, said cylinder being in communication with the barrel, a secondcylinder in parallelism with the barrel and disposed to one sidethereof, a power storing means comprising a piston movable in saidcylinder and a spring compressed by the movement of said piston, amember carried by one of said rods,

cam means actuated by the power storing means 7 for moving said memberto move the rod in such manner as to initially move the breech blockaway from the magazine and thereafter move the magazine away from thebarrel, a dashpot comprising a cylinder, a piston therein, a piston rodcarried by said piston, a spring tending to thrust said piston rodoutwardly, a circuit closing means in the path of movement of saidpiston rod adapted to be closed at the completion of the outwardmovement of said piston rod, and means for locking the piston rod andthe power storing means together in such manner as to open the circuitduring the initial reverse movement of the piston rod and to cause thedashpot to retard the return movement of the power storing means, ascavenging element upon the barrel, and means carried by the powerstoring means for actuating the scavenging element during the returnmovement of the power storing means.

18. A device of the character described comprising a main barrelconstituting a combustion chamber, a magazine adapted to hold aplurality .of unit charges adapted to generate fluid pressure whenignited and burned, means for automatically bringing each unit chargesuccessively into operative relation with said combustionchamber, meansfor discharging a unit charge into said chamber when in operativeposition, means operated in one direction by pressure from within saidcombustion chamberjor storing up power for the return stroke of saidmeans to normal position, cam means operated during the return stroke ofsaid power storing means for partially rotating the magazine to bringthe next unit charge in proper position for firing, and a I dashpotmechanism operated to control the return stroke of said power storingmeans.

19. A device of the character described comprising a main barrelconstituting a combustion chamber, a magazine adapted to hold aplurality of unit charges adapted to generate fluid atedduring thereturn stroke of said power stor.

ing means for partially rotating the magazine to bring the next unitcharge in proper position for finng, and a dashpot mechanism operativeto control the return stroke of said power storing means and alsoeffective to maintain the automatic switch in open position during thereturn stroke of the power storing means to thereby prevent prematurefiring of a unit charge.

20. A device of the character descrited comprising a main barrelconstituting acombustion chamber, a magazine adapted to hold a pluralityof unit charges adapted to generate fluid pressure when ignited andburned, a firing pin and breech block mechanism associated with saidmagazine and adapted to cooperate with eachof said unit charges insuccession forigniting the same, mechanism for intermittently rotatingsaid magazine step by step to automatically position each unit chargesuccessively into operative re-.

lation with said combustion chamber, means for discharging a unit chargeinto said chamber when in operative position, and a power operated camslide, cooperating with parts of the magazine structure to move thebreech block mechanism away from the magazine and while maintaining saidrelationship to thereafter move the magazine away from the barrel andprior to the turning movement of said magazine for the purposesintended.

ROSCOE ALEXANDER COFFMAN.

